Climate change is forcing wildlife to move north — and they're bringing diseases with them | Canada News Media
Connect with us

Health

Climate change is forcing wildlife to move north — and they’re bringing diseases with them

Published

 on

COVID-19 has shown us how quickly a new disease can spread, upending our lives. Even if it doesn’t happen within our lifetimes, research suggests there will be another pandemic and it will likely happen through a disease that reaches humans from animals.

In Canada, the risk of diseases being passed from animals to humans is relatively low — but not zero. Based on existing trends, some scientists expect the rate of emergence of new diseases to triple over the next several decades due to increased interaction between humans and animals.

Invasive species — those that enter a new habitat and out-compete native wildlife — may also bring new diseases, which can be devastating.

With both native and invasive species often having no choice but to move through densely populated areas when searching for new habitats, there is a higher risk of those diseases being passed from animals to humans.

This is known as zoonosis.

Zoonosis events can lead to outbreaks of novel diseases, such as SARS-CoV-2, the virus that causes COVID-19.

Scientists have estimated there are over 10,000 viruses with the potential to infect humans and that are currently residing in animal hosts — and that doesn’t include bacteria or other pathogens.

A recent paper published in the journal Nature shows climate change is increasing the risk of those viruses crossing the species barrier and infecting humans.

In other cases, known carriers of existing human diseases are being given the opportunity to move into new areas, increasing the risk of transmission.

Here in Canada, many native and invasive species can host and transmit diseases — one of many reasons scientists are wary of species expanding into new areas.

Enter the blacklegged tick, Ixodes scapularis, found across the eastern provinces, and its cousin the western blacklegged tick, Ixodes pacificus, found on the Pacific Coast.

Blacklegged ticks are smaller than the common brown dog tick and can be vectors for Lyme disease. (Ben Garver/The Berkshire Eagle via The Associated Press)

Though not likely to cause a pandemic, in Canada, they are the only known carriers of Borrelia burgdorferi, the bacteria that causes Lyme disease, which has been on the rise over the past decade.

They can carry a variety of other pathogens as well.

Blacklegged ticks, also known as deer ticks, were once a rare sight across Canada. Today, they are found across large parts of Ontario and other provinces, and more during the year than ever before.

Catherine Bouchard, a veterinary epidemiologist with the Public Health Agency of Canada and adjunct professor at the University of Montreal, has seen this first hand.

“Fifteen years ago … sampling for over six months per year, I would find maybe 1,000 ticks over a two-year period,” said Bouchard, who works primarily in the Estrie region of Quebec. “Nowadays, when we go out there in the same region … within two months, we are getting 1,000 ticks.”

This is the same trend seen across much of Canada, including Ontario, and Bouchard said it is expected to continue.

This has also led to a major increase in the number of cases of Lyme disease — an inflammatory disease that can start as a rash, headache, fever and chills, and develop into more serious issues like arthritis, long-lasting fatigue, and neurological and cardiac problems.

In order to transmit Lyme disease, a tick must remain attached for at least 24 hours, with the chance of transmission increasing significantly the longer it feeds, said Bouchard.

She added that although only about 20 per cent of ticks carry the disease-causing bacteria on average, it can be as high as 50 per cent in some areas.

Reported cases of Lyme disease across Ontario and Canada have been rising over the last decade. The data is from Public Health Ontario and the Public Health Agency of Canada. (CBC News)

Moving to new areas

These ticks are one of many species undergoing a range shift — moving north because of climate change.

“With key climate change drivers such as temperature but also precipitation … the weather that we are experiencing, that is changing, of course it has a direct impact on vector ticks,” said Bouchard.

A range shift occurs when species are forced to move out of their typical homes and into new areas that can support them.

You can see an example of that in Ontario, where blacklegged tick populations have spread since 2016.

Estimated Lyme disease risk areas in Ontario have been growing since 2016. These risk areas are based on where blacklegged ticks are found during active sampling by researchers. (CBC News)

Every species has a niche — a specific set of environmental constraints that must be met for survival and to reproduce. These include temperature, humidity, precipitation and the presence or absence of certain other species.

Climate change has affected these factors in habitats around the world. As a result, many species’ niches are less common or no longer exist within their historical range.

“Because of climate change, the conditions are changing throughout the range of all the species, and what was the region where they were having their optimum of abundance is shifting,” said Marie-Josée Fortin, a professor of ecology and evolutionary biology at the University of Toronto.

“[Species] are finding that the location where they are is too hot, or too dry or too humid for them, so they have to move.”

Movement can be unpredictable, but generally, species tend to head toward cooler climates: toward the poles, to higher elevations or in the case of aquatic species, to lower depths.

These range shifts pose many challenges for individual species, ecosystems and even human communities.

Movement isn’t always easy

For some species, like caribou or migratory birds, movement is a natural part of their lives.

“They are used to moving through large regions,” Fortin said. “But other species, they cannot move that fast, right? So they need to slowly acquire some new habitat along the way.”

These discrepancies between species’ abilities to move to new habitats can make range shifts difficult even for those that can move with relative ease.

Not only do species need to have the right climate — they also need their resources, food and other members of their species to survive, Fortin explained.

New areas also mean new competition with new species, including humans.

“If you think of species from southern Ontario that are at the northern range of their limit in North America, to move north, what they are faced with is an agricultural landscape, so there’s not much habitat to colonize,” said Fortin.

“They are competing with humans for the best habitat that they could use.”

Even when trying to return land to its natural state by rehabilitating areas with native species, climate change is a big part of the conversation, said Tys Theysmeyer, head of natural lands at the Royal Botanical Gardens (RBG) in Hamilton.

That’s why more northern species, like hemlock trees, may not be part of planting efforts at the RBG in the future, even though they’re native to the area.

Many animals are capable of carrying and spreading invasive species to new areas. They include this common yellowthroat with ticks around its eyes. In the past, invasive species may have died in colder habitats, but climate change may allow them to establish themselves in new areas as they warm. (Submitted by Catherine Bouchard)

“We’re starting to think a little more about those slightly more southern plants as part of site restoration projects,” said Theysmeyer.

“And at the same time, you’re looking at, well, what are the trees that will march north into this area and be the foundation of the future forest.”

Range shifts can entail contractions or expansions

For many species, the term “range shift” is a bit of a misnomer.

Species at risk often face what is better described as a range contraction — where their southern range border moves faster than the northern one, causing its range to shrink.

This is also common for species that live on mountains. As the climate warms, their range shifts to a higher elevation, but eventually there is no mountain left to ascend.

Meanwhile, range shifts may drive other species to become invasive, harming other ecosystems they enter.

Indeed, invasive species, like blacklegged ticks, often enjoy range expansion as a result of climate change, as they gain more suitable habitat than they lose.

Even for migratory species like caribou, it can be difficult to travel through human-dominated landscapes. (Danita Delmont/Shutterstock)

For many protected areas, removal of invasive species is a top priority.

Climate change is threatening to make that even more difficult.

“In the climate we have, it’s usually the cold that [keeps invasive species away],” said Theysmeyer. “If the climate doesn’t get as cold, then what limits your survival in the winter no longer limits your survival and you start to move in.

“The impacts that we worry about more than anything are the Eurasian insects, or bacteria or plants that have made it to North America and are invasive species, but are held at bay by the fact that it gets too cold here in the winter,” he said.

“It’s definitely a thing we’re watching, everybody’s watching.”

Monitoring and solutions

Work is underway through research networks to track and monitor these shifts.

“By having these big networks of research, trying to track these emerging diseases, and I think that’s how we have a chance — just by doing that collective work, collective effort of all these different partners,” said Bouchard.

Disease emergence and pandemic vigilance have become a key focus of many jurisdictions in the wake of COVID-19, with the public, scientists and policymakers alike recognizing the dangers of being caught unaware.

Tys Theysmeyer, head of natural lands at the Royal Botanical Gardens in Hamilton, says the RBG has to make hard decisions about which species to use in habitat restoration efforts based on whether they can survive in the RBG long term in the face of climate change. (Darius Mahdavi/CBC)

As for those working on the ground to help species affected by range shifts, it really comes down to helping nature do its thing.

One of the best ways to do this is to provide corridors or stepping stones of natural habitat so species can move across human-dominated landscapes to new habitats.

“Parks Canada has an initiative to create some corridors throughout the country,” Fortin said. “But it’s a work in progress.”

When restoring these areas, diversity is key.

“Rebuilding ecosystems is mostly about building resilience,” said Theysmeyer of the RBG.  “The greater diversity you can have, the better.”

Source link

Continue Reading

Health

Health Canada approves updated Moderna COVID-19 vaccine

Published

 on

 

TORONTO – Health Canada has authorized Moderna’s updated COVID-19 vaccine that protects against currently circulating variants of the virus.

The mRNA vaccine, called Spikevax, has been reformulated to target the KP.2 subvariant of Omicron.

It will replace the previous version of the vaccine that was released a year ago, which targeted the XBB.1.5 subvariant of Omicron.

Health Canada recently asked provinces and territories to get rid of their older COVID-19 vaccines to ensure the most current vaccine will be used during this fall’s respiratory virus season.

Health Canada is also reviewing two other updated COVID-19 vaccines but has not yet authorized them.

They are Pfizer’s Comirnaty, which is also an mRNA vaccine, as well as Novavax’s protein-based vaccine.

This report by The Canadian Press was first published Sept. 17, 2024.

Canadian Press health coverage receives support through a partnership with the Canadian Medical Association. CP is solely responsible for this content.

The Canadian Press. All rights reserved.

Source link

Continue Reading

Health

These people say they got listeria after drinking recalled plant-based milks

Published

 on

 

TORONTO – Sanniah Jabeen holds a sonogram of the unborn baby she lost after contracting listeria last December. Beneath, it says “love at first sight.”

Jabeen says she believes she and her baby were poisoned by a listeria outbreak linked to some plant-based milks and wants answers. An investigation continues into the recall declared July 8 of several Silk and Great Value plant-based beverages.

“I don’t even have the words. I’m still processing that,” Jabeen says of her loss. She was 18 weeks pregnant when she went into preterm labour.

The first infection linked to the recall was traced back to August 2023. One year later on Aug. 12, 2024, the Public Health Agency of Canada said three people had died and 20 were infected.

The number of cases is likely much higher, says Lawrence Goodridge, Canada Research Chair in foodborne pathogen dynamics at the University of Guelph: “For every person known, generally speaking, there’s typically 20 to 25 or maybe 30 people that are unknown.”

The case count has remained unchanged over the last month, but the Public Health Agency of Canada says it won’t declare the outbreak over until early October because of listeria’s 70-day incubation period and the reporting delays that accompany it.

Danone Canada’s head of communications said in an email Wednesday that the company is still investigating the “root cause” of the outbreak, which has been linked to a production line at a Pickering, Ont., packaging facility.

Pregnant people, adults over 60, and those with weakened immune systems are most at risk of becoming sick with severe listeriosis. If the infection spreads to an unborn baby, Health Canada says it can cause miscarriage, stillbirth, premature birth or life-threatening illness in a newborn.

The Canadian Press spoke to 10 people, from the parents of a toddler to an 89-year-old senior, who say they became sick with listeria after drinking from cartons of plant-based milk stamped with the recalled product code. Here’s a look at some of their experiences.

Sanniah Jabeen, 32, Toronto

Jabeen says she regularly drank Silk oat and almond milk in smoothies while pregnant, and began vomiting seven times a day and shivering at night in December 2023. She had “the worst headache of (her) life” when she went to the emergency room on Dec. 15.

“I just wasn’t functioning like a normal human being,” Jabeen says.

Told she was dehydrated, Jabeen was given fluids and a blood test and sent home. Four days later, she returned to hospital.

“They told me that since you’re 18 weeks, there’s nothing you can do to save your baby,” says Jabeen, who moved to Toronto from Pakistan five years ago.

Jabeen later learned she had listeriosis and an autopsy revealed her baby was infected, too.

“It broke my heart to read that report because I was just imagining my baby drinking poisoned amniotic fluid inside of me. The womb is a place where your baby is supposed to be the safest,” Jabeen said.

Jabeen’s case is likely not included in PHAC’s count. Jabeen says she was called by Health Canada and asked what dairy and fresh produce she ate – foods more commonly associated with listeria – but not asked about plant-based beverages.

She’s pregnant again, and is due in several months. At first, she was scared to eat, not knowing what caused the infection during her last pregnancy.

“Ever since I learned about the almond, oat milk situation, I’ve been feeling a bit better knowing that it wasn’t something that I did. It was something else that caused it. It wasn’t my fault,” Jabeen said.

She’s since joined a proposed class action lawsuit launched by LPC Avocates against the manufacturers and sellers of Silk and Great Value plant-based beverages. The lawsuit has not yet been certified by a judge.

Natalie Grant and her seven year-old daughter, Bowmanville, Ont.

Natalie Grant says she was in a hospital waiting room when she saw a television news report about the recall. She wondered if the dark chocolate almond milk her daughter drank daily was contaminated.

She had brought the girl to hospital because she was vomiting every half hour, constantly on the toilet with diarrhea, and had severe pain in her abdomen.

“I’m definitely thinking that this is a pretty solid chance that she’s got listeria at this point because I knew she had all the symptoms,” Grant says of seeing the news report.

Once her daughter could hold fluids, they went home and Grant cross-checked the recalled product code – 7825 – with the one on her carton. They matched.

“I called the emerg and I said I’m pretty confident she’s been exposed,” Grant said. She was told to return to the hospital if her daughter’s symptoms worsened. An hour and a half later, her fever spiked, the vomiting returned, her face flushed and her energy plummeted.

Grant says they were sent to a hospital in Ajax, Ont. and stayed two weeks while her daughter received antibiotics four times a day until she was discharged July 23.

“Knowing that my little one was just so affected and how it affected us as a family alone, there’s a bitterness left behind,” Grant said. She’s also joined the proposed class action.

Thelma Feldman, 89, Toronto

Thelma Feldman says she regularly taught yoga to friends in her condo building before getting sickened by listeria on July 2. Now, she has a walker and her body aches. She has headaches and digestive problems.

“I’m kind of depressed,” she says.

“It’s caused me a lot of physical and emotional pain.”

Much of the early days of her illness are a blur. She knows she boarded an ambulance with profuse diarrhea on July 2 and spent five days at North York General Hospital. Afterwards, she remembers Health Canada officials entering her apartment and removing Silk almond milk from her fridge, and volunteers from a community organization giving her sponge baths.

“At my age, 89, I’m not a kid anymore and healing takes longer,” Feldman says.

“I don’t even feel like being with people. I just sit at home.”

Jasmine Jiles and three-year-old Max, Kahnawake Mohawk Territory, Que.

Jasmine Jiles says her three-year-old son Max came down with flu-like symptoms and cradled his ears in what she interpreted as a sign of pain, like the one pounding in her own head, around early July.

When Jiles heard about the recall soon after, she called Danone Canada, the plant-based milk manufacturer, to find out if their Silk coconut milk was in the contaminated batch. It was, she says.

“My son is very small, he’s very young, so I asked what we do in terms of overall monitoring and she said someone from the company would get in touch within 24 to 48 hours,” Jiles says from a First Nations reserve near Montreal.

“I never got a call back. I never got an email”

At home, her son’s fever broke after three days, but gas pains stuck with him, she says. It took a couple weeks for him to get back to normal.

“In hindsight, I should have taken him (to the hospital) but we just tried to see if we could nurse him at home because wait times are pretty extreme,” Jiles says, “and I don’t have child care at the moment.”

Joseph Desmond, 50, Sydney, N.S.

Joseph Desmond says he suffered a seizure and fell off his sofa on July 9. He went to the emergency room, where they ran an electroencephalogram (EEG) test, and then returned home. Within hours, he had a second seizure and went back to hospital.

His third seizure happened the next morning while walking to the nurse’s station.

In severe cases of listeriosis, bacteria can spread to the central nervous system and cause seizures, according to Health Canada.

“The last two months have really been a nightmare,” says Desmond, who has joined the proposed lawsuit.

When he returned home from the hospital, his daughter took a carton of Silk dark chocolate almond milk out of the fridge and asked if he had heard about the recall. By that point, Desmond says he was on his second two-litre carton after finishing the first in June.

“It was pretty scary. Terrifying. I honestly thought I was going to die.”

Cheryl McCombe, 63, Haliburton, Ont.

The morning after suffering a second episode of vomiting, feverish sweats and diarrhea in the middle of the night in early July, Cheryl McCombe scrolled through the news on her phone and came across the recall.

A few years earlier, McCombe says she started drinking plant-based milks because it seemed like a healthier choice to splash in her morning coffee. On June 30, she bought two cartons of Silk cashew almond milk.

“It was on the (recall) list. I thought, ‘Oh my God, I got listeria,’” McCombe says. She called her doctor’s office and visited an urgent care clinic hoping to get tested and confirm her suspicion, but she says, “I was basically shut down at the door.”

Public Health Ontario does not recommend listeria testing for infected individuals with mild symptoms unless they are at risk of developing severe illness, such as people who are immunocompromised, elderly, pregnant or newborn.

“No wonder they couldn’t connect the dots,” she adds, referencing that it took close to a year for public health officials to find the source of the outbreak.

“I am a woman in my 60s and sometimes these signs are of, you know, when you’re vomiting and things like that, it can be a sign in women of a bigger issue,” McCombe says. She was seeking confirmation that wasn’t the case.

Disappointed, with her stomach still feeling off, she says she decided to boost her gut health with probiotics. After a couple weeks she started to feel like herself.

But since then, McCombe says, “I’m back on Kawartha Dairy cream in my coffee.”

This report by The Canadian Press was first published Sept. 16, 2024.

Canadian Press health coverage receives support through a partnership with the Canadian Medical Association. CP is solely responsible for this content.

Source link

Continue Reading

Health

B.C. mayors seek ‘immediate action’ from federal government on mental health crisis

Published

 on

 

VANCOUVER – Mayors and other leaders from several British Columbia communities say the provincial and federal governments need to take “immediate action” to tackle mental health and public safety issues that have reached crisis levels.

Vancouver Mayor Ken Sim says it’s become “abundantly clear” that mental health and addiction issues and public safety have caused crises that are “gripping” Vancouver, and he and other politicians, First Nations leaders and law enforcement officials are pleading for federal and provincial help.

In a letter to Prime Minister Justin Trudeau and Premier David Eby, mayors say there are “three critical fronts” that require action including “mandatory care” for people with severe mental health and addiction issues.

The letter says senior governments also need to bring in “meaningful bail reform” for repeat offenders, and the federal government must improve policing at Metro Vancouver ports to stop illicit drugs from coming in and stolen vehicles from being exported.

Sim says the “current system” has failed British Columbians, and the number of people dealing with severe mental health and addiction issues due to lack of proper care has “reached a critical point.”

Vancouver Police Chief Adam Palmer says repeat violent offenders are too often released on bail due to a “revolving door of justice,” and a new approach is needed to deal with mentally ill people who “pose a serious and immediate danger to themselves and others.”

This report by The Canadian Press was first published Sept. 16, 2024

The Canadian Press. All rights reserved.

Source link

Continue Reading

Trending

Exit mobile version